<script type="module">
  import {
    createApp,
    ref,
  } from 'https://unpkg.com/vue@3/dist/vue.esm-browser.js'
  //   import DemoVue from './DemoVue.js'
  createApp({
    setup() {
      const txt = ref('1123')
      return { txt }
    },
  }).mount('#app')
</script>

<div id="app">{{txt}}</div>
